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AIRNA’s total capital raised so far is $245m. Credit: sesame via Getty Images. AIRNA has raised $155m in Series B financing to advance its RNA editing pipeline, and kick-start a clinical trial for its lead candidate, AIR-001. Venrock Healthcare Capital Partners and Forbion Growth co-led the new round, bringing AIRNA’s total raised capital to $245m. The US and Germany-based biotech plans to file a clinical trial application (CTA) for its lead candidate, AIR-001, for alpha-1 antitrypsin deficiency (AATD) by H2 2025. The company is developing AIR-001 as an investigational RNA editor – a therapy designed to modify RNA sequences to correct disease-causing mutations. This approach is different to DNA editing approaches such as clustered regularly interspaced short palindromic repeats (CRISPR), which make permanent changes to the genome. RNA editing is a reversible process that allows for targeted corrections without altering the underlying genetic code. The Series B funds will support the launch of a Phase I/II clinical trial for AIR-001 and the further development of other RNA-editing candidates, primarily targeting cardiometabolic diseases. AATD is a rare genetic disorder caused by mutations in the SERPINA1 gene, which encodes the AAT protein. Under normal circumstances, AAT is produced in the liver and transported to the lungs, where it regulates enzyme activity to prevent tissue damage. In patients with AATD, mutations can prevent AAT from exiting the liver, leading to toxic protein accumulation that damages the liver while also depriving the lungs of necessary protection. This can result in progressive lung disease, liver dysfunction, and symptoms such as shortness of breath, fatigue, and jaundice. The AATD treatment landscape is becoming increasingly competitive as multiple biotechs advance RNA-editing candidates. Korro Bio is investigating its candidate KRRO-110 in the Phase I/IIa REWRITE clinical trial (NCT06677307), with interim data expected in H2 2025. The company announced last month that the dosing of the first two cohorts had been completed, and the trial is expected to conclude next year. Wave Life Sciences is developing WVE-006, which demonstrated targeted RNA editing in the first two patients treated in the Phase Ib/IIa RestorAATion-2 clinical trial (NCT06405633). The growing interest in RNA editing has also drawn investment from major pharmaceutical companies. In November 2023, Roche expanded its partnership to develop a one-time RNA editing therapy using ShapeTX’s AI-powered platform for an undisclosed disease. In September 2024, Novo Nordisk and Korro Bio announced a collaboration leveraging Korro’s OPERA platform to enable oligonucleotide-directed RNA edits for two undisclosed targets, initially focused on cardiometabolic diseases. The deal included up to $530m in upfront, development, and commercial milestone payments, along with tiered royalties and R&D funding. Not all genetic medicine approaches for AATD have progressed as planned. In January 2025, Intellia Therapeutics discontinued the development of its CRISPR-based gene therapy NTLA-3001, which was intended to correct the SERPINA1 mutation at the DNA level. Preparations for the Phase I/II trial were halted, along with other early-stage programmes, signalling a shift in the company’s pipeline priorities. With fresh funding and a CTA planned for later this year, AIRNA is positioning itself within the growing RNA editing field. Forbion managing partner Dirk Kersten said: “AIRNA’s innovative approach to RNA editing has the distinctive potential to improve health across large populations by introducing healthy genetic variants for many conditions. We are excited to support the expansion of AIRNA’s pipeline of life-changing medicines and the advancement of AIR-001 into the clinic.”

AIRNA is focused on genetic variations that cause disease, plus using precision editing tech to tweak RNA into more healthy variations.\n AIRNA, a transatlantic RNA editing biotech, is prepping to launch its lead asset into clinical trials with fuel from a $155 million series B fundraise.The round was led by Venrock Healthcare Capital Partners and Forbion Growth, AIRNA announced in an April 1 release. Forbion had previously led AIRNA’s $60 million financing in July 2024. Other investors in the most recent round include RTW Investments, Arch Venture Partners, Nextech Invest, Forbion Ventures, ND Capital and other unnamed investors.  The series B cash will go toward launching a phase 1/2 trial for AIR-001, AIRNA’s drug candidate for alpha-1 antitrypsin deficiency (AATD), and will also help bolster the company’s early pipeline of RNA editing therapeutics.AIRNA plans to ask for approval to enter AIR-001 into clinical trials in the second half of this year, the company’s CEO Kris Elverum told Fierce Biotech in an interview. Elverum declined to disclose more information about the trial’s design and timeline.The biotech is also working to advance other preclinical programs that stem from AIRNA’s proprietary platform, Elverum added, including one in cardiometabolic disease.The company, headquartered in Cambridge, Massachusetts, with a subsidiary in Tübingen, Germany, was founded in 2021 and is open to partnerships with larger companies, according to the CEO.“There\'s only so much we\'re able to do as a small company,” Elverum said. “There are other companies that have capabilities in certain areas that would be better suited for bringing novel medicines to patients.”That being said, AIRNA remains committed to “building a significant and distinctive biopharma company for the long term,” Elverum added. AIRNA\'s lead asset is designed to treat AATD, a lung and liver disease that is caused by a mutated copy of the SERPINA1 gene, which leads to low levels of the protective alpha-1 antitrypsin (AAT) protein in the blood. AAT is made in the liver but ultimately migrates to the lungs; without enough of the protein, patients with AATD experience lung symptoms like coughing and shortness of breath. Malfunctioning AAT can also build up in the liver and cause cirrhosis, and patients with AATD may ultimately need a lung or liver transplant.The most common causative mutation of AATD is called PiZ, which is when an adenosine occurs at a site in the gene’s DNA instead of a guanosine. AIR-001 aims to fix this glitch by swapping the errant adenosine for a nucleotide called inosine, which the body treats the same as a guanosine.“We\'re able to repair the mutation for alpha-1 antitrypsin deficiency through this approach to give patients what we believe will be a functional cure,” Elverum said.AIRNA’s platform takes advantage of an enzyme that can be found in all of our cells, called adenosine deaminase acting on RNA (ADAR). AIRNA cofounder Thorsten Stafforst, Ph.D., a biochemist at the University of Tübingen in Germany, published a paper in 2019 demonstrating that oligonucleotides can be used to recruit ADAR to make targeted adenosine-to-inosine edits in RNA.Though AIRNA’s founders have also studied other RNA editing mechanisms, AIRNA is focused solely on harnessing ADAR.“Our data would indicate that there\'s a wide swath of opportunities for making multiple medicines with that one A to I letter change,” Elverum said.With AATD and other genetic conditions, AIRNA is focused on genetic variations that cause disease. But the company is also interested in using its precision editing tech to tweak RNA into more healthy variations.“It\'s the 90-year-old smoker who doesn\'t develop heart disease. Why is that?” Elverum said. “As a team, we\'ve spent a lot of time identifying these healthy variants and our data would indicate that we can recapitulate the positive physiological effects of these healthy variants through a single RNA edit.” AIR-001 requires regular subcutaneous doses, because editing RNA is not permanent the way editing DNA is. Elverum sees the temporary nature of RNA editing as a distinct advantage to the approach over one-and-done DNA editing gene therapies. “People want to maintain control over their health,” Elverum said. With RNA editing therapies, patients can work with their physicians to adjust dosing and find what works best for them, he added, or stop taking the medicine entirely if they want.Elsewhere in the industry, a one-and-done gene therapy for AATD from Beam Therapeutics recently saw early success in a phase 1/2 trial, appearing to correct the PiZ mutation in nine patients, with no serious adverse events reported. Beam\'s trial is expected to enroll about 106 adult patients with AATD and is taking place in two parts. The first part includes patients with AATD and lung disease, while the second part will include patients with AATD, plus patients with AATD that also have mild to moderate liver disease.